The Constitution says nothing about a separation of Church and state, and while it may be to your liking, there is no basis upon which you could consider it Constitutional to ban, for instance, a nativity scene on public property.
Yes, there is, and clearly so. Setting up the nativity scene qualifies as an "establishment of a state religion."
Christmas is a national, I will go so far as to say a Federal, holiday.
As I said, something like this will not be perfect, and there is no one single objective standard to apply.
This is no more an establishment of religion than if a Buddhist statue were to be temporarily, or even permanently, displayed on the grounds of the Washington monument....
A permanent installation of a statute of the Buddha is, without question, an "establishment of a state religion." It doesn't matter if it seems
to you that there are so few Buddhists, with so little influence in society. It is still sending a message that "the state endorses Buddhism."
If a group is conducting a Buddhist ritual on the Mall, and temporarily set up a statue of the Buddha, that's fine. They are acting as individuals, and using a public space, without any hint of endorsement from the government. No one is putting a halt to that kind of activity.
There should be no reason, for instance, for people to be fearful of expressing their faith openly in school settings.
If you're talking about a group of students who meet before classes and pray, then (afaik) that's perfectly legitimate.
If the school sets aside class time and says "you have the option to pray for the next 5 minutes," then that's an establishment of religion, and should be (and is) barred.
In classrooms students should not be discouraged from putting forth their own opinions about whether, as our textbooks say, man is related to, descended from and/or derives from other species...
If by "discouraged" you mean "allowed to speak their opinions," yes. However, the official science curriculum should not be teaching students that Adam was made by God out of dust, nor should a student be exempted from learning about evolution if they attend a public school.
especially when this cannot and, under rigorous scientific method, is not even close to being near proven as fact.
Evolution is a fact. There is abundant scientific evidence to support it. There is absolutely no doubt whatsoever that human beings evolved from earlier primates, and that we are still evolving. It is as certain as "heating water to 100º C will turn the water into steam." Your own ignorance on this matter is really not helping your case.
government does not have the right to suppress what individuals really think.
Government also is not, and should not be, empowered to teach people supernatural beliefs in a science class.
I would agree that no religion should be proselytized, but defense of faith should specifically be allowed.
...and that "defense of faith" is, again, an act of establishing a religion. Thus, it's out.
And specifically, why cannot/should not the Ten Commandments be displayed...
Because
that's an establishment of religion. That should be
screamingly obvious.
I mean, seriously, have you not read them lately? Do you really not remember that #1 is “You shall have no other gods before me" ?
many of our laws are indirectly based on this....
Oh? Is it illegal to make a graven image of God? No? Are we criminalizing adultery again? Will I be arrested for blasphemy? Is coveting a misdemeanor or a felony?